シッフ塩基、Schiff塩基

WordNet

any of various water-soluble compounds capable of turning litmus blue and reacting with an acid to form a salt and water; "bases include oxides and hydroxides of metals and ammonia" (同)alkali
(numeration system) the positive integer that is equivalent to one in the next higher counting place; "10 is the radix of the decimal system" (同)radix
the bottom side of a geometric figure from which the altitude can be constructed; "the base of the triangle"
situate as a center of operations; "we will base this project in the new lab"
a place that the runner must touch before scoring; "he scrambled to get back to the bag" (同)bag
installation from which a military force initiates operations; "the attack wiped out our forward bases" (同)base of operations
a support or foundation; "the base of the lamp" (同)pedestal, stand
(electronics) the part of a transistor that separates the emitter from the collector
a flat bottom on which something is intended to sit; "a tub should sit on its own base"
the principal ingredient of a mixture; "glycerinated gelatin is used as a base for many ointments"; "he told the painter that he wanted a yellow base with just a hint of green"; "everything she cooked seemed to have rice as the base"
the place where you are stationed and from which missions start and end (同)home
(anatomy) the part of an organ nearest its point of attachment; "the base of the skull"
the bottom or lowest part; "the base of the mountain"
illegitimate (同)baseborn
of low birth or station (`base is archaic in this sense); "baseborn wretches with dirty faces"; "of humble (or lowly) birth" (同)baseborn, humble, lowly
not adhering to ethical or moral principles; "base and unpatriotic motives"; "a base, degrading way of life"; "cheating is dishonorable"; "they considered colonialism immoral"; "unethical practices in handling public funds" (同)immoral
having or showing an ignoble lack of honor or morality; "that liberal obedience without which your army would be a base rabble"- Edmund Burke; "taking a mean advantage"; "chokd with ambition of the meaner sort"- Shakespeare; "something essentially vulgar and meanspirited in politics" (同)mean, meanspirited
(used of metals) consisting of or alloyed with inferior metal; "base coins of aluminum"; "a base metal"
debased; not genuine; "an attempt to eliminate the base coinage"
having a base; "firmly based ice"
having a base of operations (often used as a combining form); "a locally based business"; "an Atlanta-based company"; "carrier-based planes"

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《文》(人や人の行動・孝えが)『卑しい』,下劣な / (金属が)質の劣った;(貨幣が)粗悪な
『基礎』,根拠 / 『基部』,基底,土台 / 『根拠地』,基地 / (野球の)塁,ベース / 主成分;塩基(酸と反応シテ塩(官)を生じる化合物) / (数学で図形の)底;底辺;基線 / (…に)…‘の'『基礎をおく』《+『名』+『on』(『upon』)+『名』》
basisの複数形

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/01/29 10:52:28」(JST)

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General structure of an azomethine

General structure of a Schiff base (narrow definition)

A Schiff base, named after Hugo Schiff, is a compound with a functional group that contains a carbon-nitrogen double bond with the nitrogen atom connected to an aryl or alkyl group, not hydrogen.^[1] Schiff bases in a broad sense have the general formula R¹R²C=NR³, where R is an organic side chain. In this definition, Schiff base is synonymous with azomethine. Some restrict the term to the secondary aldimines (azomethines where the carbon is connected to a hydrogen atom), thus with the general formula RCH=NR'.^[2]

The chain on the nitrogen makes the Schiff base a stable imine. A Schiff base derived from an aniline, where R³ is a phenyl or a substituted phenyl, can be called an anil.^[3]

Synthesis[edit]

Schiff bases can be synthesized from an aliphatic or aromatic amine and a carbonyl compound by nucleophilic addition forming a hemiaminal, followed by a dehydration to generate an imine. In a typical reaction, 4,4'-diaminodiphenyl ether reacts with o-vanillin:^[4]

A mixture of 4,4'-diaminodiphenyl ether 1 (1.00 g, 5.00 mmol) and o-vanillin 2 (1.52 g, 10.00 mmol) in methanol (40.00 mL) is stirred at room temperature for one hour to give an orange precipitate and after filtration and washing with methanol to give the pure Schiff base 3 (2.27 g, 97.00%)

Biochemistry[edit]

Schiff bases are common enzymatic intermediates where an amine, such as the terminal group of a lysine residue reversibly reacts with an aldehyde or ketone of a cofactor or substrate. The common enzyme cofactor PLP forms a Schiff base with a lysine residue and is transaldiminated to the substrate(s).^[5] Similarly, the cofactor retinal forms a Schiff base in rhodopsins, including human rhodopsin (via Lysine 296), which is key in the photoreception mechanism.

An example where the substrate forms a Schiff base to the enzyme is in the fructose 1,6-bisphosphate aldolase catalyzed reaction during glycolysis and in the metabolism of amino acids.

Coordination chemistry[edit]

Schiff bases are common ligands in coordination chemistry. The imine nitrogen is basic and exhibits pi-acceptor properties. The ligands are typically derived from alkyl diamines and aromatic aldehydes.^[6]

Schiff base ligands

Copper(II) complex of the Schiff base ligand salicylaldoxime.

Salen is a common tetradentate ligand, it becomes deprotonated upon complexation.

Jacobsen's catalyst is derived from a chiral salen ligand.

Chiral Schiff bases were one of the first ligands used for asymmetric catalysis. In 1968 Ryōji Noyori developed a copper-Schiff base complex for the metal-carbenoid cyclopropanation of styrene.^[7] For this work he was later awarded a share of the 2001 Nobel Prize in Chemistry.

References[edit]

^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "Schiff base".
^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "azomethines".
^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "anils".
^ Jarrahpour, A. A.; M. Zarei (February 24, 2004). "Synthesis of 2-({[4-(4-{[(E)-1-(2-hydroxy-3-methoxyphenyl)methylidene amino}phenoxy)phenyl imino}methyl)- 6 -methoxy phenol". Molbank M352. ISSN 1422-8599. Retrieved February 22, 2010. Cite uses deprecated parameters (help)
^ Eliot, A. C.; Kirsch, J. F. (2004). "PYRIDOXALPHOSPHATEENZYMES: Mechanistic, Structural, and Evolutionary Considerations". Annual Review of Biochemistry 73: 383–415. doi:10.1146/annurev.biochem.73.011303.074021. PMID 15189147. edit
^ R. Hernández-Molina, A. Mederos "Acyclic and Macrocyclic Schiff Base Ligands" in Comprehensive Coordination Chemistry II 2003, Pages 411–446. doi:10.1016/B0-08-043748-6/01070-7
^ H. Nozaki, H. Takaya, S. Moriuti, R. Noyori (1968). "Homogeneous catalysis in the decomposition of diazo compounds by copper chelates: Asymmetric carbenoid reactions". Tetrahedron 24 (9): 3655–3669. doi:10.1016/S0040-4020(01)91998-2.

UpToDate Contents

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1. 出産時の臍帯血酸塩基分析 umbilical cord blood acid base analysis at delivery
2. 単純性および混合性酸塩基障害 simple and mixed acid base disorders
3. 酸塩基障害におけるカリウムバランス potassium balance in acid base disorders
4. 糖尿病における血糖コントロールの評価 estimation of blood glucose control in diabetes mellitus
5. アルコール性肝疾患の病因 pathogenesis of alcoholic liver disease

English Journal

Synthesis, spectroscopic characterization, DNA interaction and antibacterial study of metal complexes of tetraazamacrocyclic Schiff base.

Shakir M, Khanam S, Firdaus F, Latif A, Aatif M, Al-Resayes SI.SourceDepartment of Chemistry, Aligarh Muslim University, Aligarh 202002, India.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy.Spectrochim Acta A Mol Biomol Spectrosc.2012 Jul;93:354-62. Epub 2012 Mar 20.
The template condensation reaction between benzil and 3,4-diaminotoulene resulted mononuclear 12-membered tetraimine macrocyclic complexes of the type, [MLCl(2)] [M=Co(II), Ni(II), Cu(II) and Zn(II)]. The synthesized complexes have been characterized on the basis of the results of elemental analysis
PMID 22484906

Developing biologically active compounds having efficient DNA binding and cleavage activity: Spectroscopic investigation.

Raman N, Sobha S.SourceResearch Department of Chemistry, VHNSN College, Virudhunagar-626 001, India.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy.Spectrochim Acta A Mol Biomol Spectrosc.2012 Jul;93:250-9. Epub 2012 Mar 18.
A new series of novel o-acetoacetotoluidide derived Schiff base and its metal complexes have been synthesized and structurally characterized. Elemental analysis, magnetic and spectroscopic data suggest that the complexes have octahedral geometry. Binding of these complexes with CT-DNA has been analy
PMID 22484260